Fused ring tetraamino compound,the tetratosylate thereof,and their synthesis

ABSTRACT

THIS INVENTION COMPRISES NEW THERMALLY STABLE POLYMERIC COMPOSITIONS, STARTING COMPOUNDS AND INTERMEDIATES AND METHODS FOR PREPARING THE SAME. THE POLYMERS ARE PREPARED BY THE CONDENSATION OF AN AROMATIC TETRAACID, SUCH AS 1,4,5,8-NAPHTHALENE TETRACARBOXYLIC ACID, AND A TETRAAMINO FUSED RING COMPOUND, NAMELY 2,3,11,12TETRAAMINO-DIQUINOXAL(2,3-E, 2&#39;&#39;,3&#39;&#39;-1)PYRENE. THIS FUSED RING TETRAAMINO COMPOUND IS PREPARED BY THE REACTION OF 1,2-DITOSYLATE OF 1,2,4,5-TETRAAMINOBENZENE WITH 1,2,6,7TETRAKETOPYRENE TO GIVE A TETRATOSYLATED DERIVATIVE WHICH AFTER TREATMENT WITH CONCNETRATED H2SO4 FOLLOWED BY BASE GIVES THE DESIRED FUSED RING TETRAMINO COMPOUND. THE TETRATOSYLATE AND THE TETRAAMINO FUSED RING COMPOUND AND THE DITOSYLATED TETRAAMINO BENZENE INTERMEDIATE ARE NEW COMPOUNDS. THE LATTER CAN BE PREPARED BY THE REDUCTION OF 1,2-DINITRO-4,5-(P-TOLUENE SULFAMIDO)BENZENE. WITH APPROPRIATE TETRAACIDS OR THEIR DERIVATIVES AND WITH SUFFICIENT REACTION OF THE REAGENTS, LADDER POLYMERS CAN BE FORMED.

United States Patent Office 3,702,326 Patented Nov. 7, 1972 3,702,326FUSED RING TETRAAMINO COMPOUND, THE TETRATOSYLATE THEREOF, AND THEIRSYNTHESIS Fred E. Arnold, Dayton, Ohio, assignor to the United States ofAmerica as represented by the Secretary of the Air Force No Drawing.Original application Apr. 16, 1969, Ser. No. 816,839, now Patent No.3,546,181. Divided and this application Aug. 5, 1970, Ser. No. 61,398

Int. Cl. C07d 51/78 U.S. Cl. 260250 R Claims ABSTRACT OF THE DISCLOSUREThis invention comprises new thermally stable polymeric compositions,starting compounds and intermediates and methods for preparing the same.The polymers are prepared by the condensation of an aromatic tetraacid,such as l,4,5,8-naphthalene tetracarboxylic acid, and a tetraamino fusedring compound, namely 2,3,11,12- tetraamino-diquinoxal(2,3-e,2',3'1)pyrene. This fused ring tetraamino compound is prepared by thereaction of 1,2-ditosylate of 1,2,4,5-tctraaminobenzene with 1,2,6,7-tetraketopyrene to give a tetratosylated derivative which aftertreatment with concentrated H 80 followed by base gives the desiredfused ring tetramino compound. The tetratosylate and the tetraaminofused ring compound and the ditosylated tetraamino benzene intermediateare new compounds. The latter can be prepared by the reduction ofl,2dinitro-4,5-(p-toluene sulfamido)benzene. With appropriate tetraacidsor their derivatives and with sufiicient reaction of the reagents,ladder polymers can be formed.

This application is a division of my application, Ser. No. 816,839,filed Apr. 16, 1969, now issued as U.S. Pat. 3,546,181.

The invention described herein may be manufactured and used by or forthe U.S. Government for governmental purposes without payment to me ofany royalty thereon.

BACKGROUND OF THE INVENTION Field of the invention The present inventionrelates to new thermally stable compositions of matter and to themethods of synthesizing the same.

The prior art is constantly searching for materials having hightemperature properties, i.e., the ability to retain their physical andchemical characteristics as well as their dimensional stability atelevated temperatures in the order of 500 C. and above. Such materialshave particular utility in a variety of aerospace applications such ason the skin or leading edges of high speed aircraft, the nose cone andheat shields of atmospheric escape and re-entry vehicles, various rocketengine components and the like. Numerous polyaromatic-heterocyclicpolymers such as the polybenzimidazoles, the polyimides and thepolybenzoxazoles, all of which possess heterocyclic nitrogen, are knownto have good thermal stability, at least upon exposure to temperaturesof approximately 500 C. in inert atmospheres. While these materials areof use in the applications above indicated and in other applicationswherein high temperature environments are anticipated, the needcontinues for additional materials having varied properties which cannonetheless withstand prolonged exposure to high temperatures; and thesearch is constantly underway for materials which are capable ofwithstanding even higher temperatures.

It is accordingly an object of this invention to provide new andimproved thermally stable compositions which will not physically orchemically deteriorate upon exposure to high temperatures in the orderof 500 C. and above in inert atmospheres.

Another object of this invention is to provide methods for synthesizingsuch materials, as well as intermediate compounds used in suchpreparations.

Description of the prior art Dawans and Marvel, J. Polymer Science, A3,3549 (1965), have disclosed the preparation of polymers by thecondensation of 1,4,5,8-tetraaminonaphthalene and1,2,4,5-tetraaminobenzene with pyromelletic anhydride.

Bell and Pendirtz, J. Polymer Science, B3, 977 (1965), and Colson etal., J. Polymer Science (A-l), 4, 59 (1966), have also disclosedpreparation of polymers by the condensation of 1,2,4,5-tetraaminobenzenewith pyromelletic acid anhydride.

However such polymers have not been completely satisfactory with regardto thermal stability and other properties.

SUMMARY OF THE INVENTION The various objects cited above and otheradvantages are achieved by the polycondensation of aromatic tetraacids,or derivatives thereof, with a new tetraamino fused ring compound,namely 2,3,11,IZ-tetraamino-diquinoxal (2,3-e, 2,3-1)pyrene.

The tetraamino fused ring compound of this invention is prepared by thecondensation of the 1,2-ditosylate of 1,2,4,5-tetraaminobenzene with1,2,6,7-tetraketopyrene, followed by acid and base treatment. Theditosylate of the tetraaminobenzene is likewise a new compound and isprepared by the hydrogenation of 1,2-dinitro-4,S-(ptoluenesulfamido)benzene by chemical reduction with sodium hydrosulfite.

The condensation reaction for production of the polymer is illustratedschematically as follows:

ll A III The Ar(COOH) represents various aromatic tetraacids in whichthe Ar nucleus can be benzene, naphthalene and pyrene, whichnon-rotatable nuclear structures can give ladder polymers, whereas othertetracids that can be used such as diphenyl tetracid can given lessrigid structures not of the ladder type. Moreover, in intermediatestructures, where only a minor number of the pairs NH2 NH Tos NO -NHTosReductwn NH,- NHTOS TosN H The expression tosylate, sometimesabbreviated as Tos, is intended to include in addition to the toluenesulfonamide derivative, other aromatic as Well as aliphatic andcycloaliphatic sulfonamide derivatives. The aromatic, cycloaliphatic andaliphatic nuclei can have various hydrocarbon radicals substitutedthereon, and the aromatic nuclei can also have halogen atoms, e.g.chlorine, bromine, iodine and fluorine, substituted thereon.Advantageously the hydrocarbon portion has no more than carbon atomstherein, since larger groups, while still reactive for this purpose,react more sluggishly.

Typical sulfonamide derivative groups are those in which the radical towhich the sulfonamide is attached are phenyl, tolyl, xylyl, naphthyl,diphenyl, methylnaphthyl, benzyl, chlorophenyl, bromophenyl, iodophenyl,fluorophenyl, chloronaphthyl, chlorodiphenyl, methyl, ethyl, propyl,amyl, octyl, decyl, dodecyl, octadecyl, cyclohexyl, cycloheptyl,methylcyclohexyl, ethylcycloheptyl, and the like.

The sulfonamide derivative groups can be introduced by any meansconvenient, but is preferably attached by reaction of the amino groupswith the appropriate sulfonyl chloride, such as toluene sulfonylchloride, benzene sulfonyl chloride, xylyl sulfonyl chloride, naphthylsulfonyl chloride, methyl sulfonyl chloride, propyl sulfonyl chloride,cyclohexyl sulfonyl chloride, and the like.

The polymer condensation reaction is preferably carried out inpolyphosphoric acid, in which case the tetraamino compound can be in theform of the free amine or in the form of the tosylate or inorganic acidsalt forms of the amine, such as the hydrochloride, the phosphate,sulfate, and the like.

Other reaction media can be used, such as aprotic" solvents, which arestrong solvents such as dimethyl formamide, dimethyl acetamide,hexamethyl phosphoramide, tetramethyl urea, dimethyl sulfoxide, and thelike. However when such aprotic solvents are used as the reaction media,the tetraamino fused ring compound should be in the free amine forminstead of the tosylate or acid salt forms that can be used with thepolyphosphoric acid.

In preparing the condensation polymers of this invention, the tetraacidand the tetraamino reagents are advantageously used in equimolaramounts, although a small excess of one or the other reagent will notadversely affect the polymerization. However, considerable excess of oneof the reagents will result in smaller molecular weight products.Generally at least two and preferably at least four of the type ofrepeating units described herein are desired in the polymer chain, withgreater number being produced upon prolonged reaction.

The temperature is advantageously in the range of 30-200 C. andgenerally a reaction period of at least 8 hours, depending on theparticular temperature, is desirable to effect a substantial conversionto polymer.

As previously indicated, the tetratosylate of the fused ring tetraaminocompound used in the polymerization is prepared by the reaction of1,2,6,7-tetraketopyrene with1,2-diamino-4,5-(p-toluenesulfamido)benzene. This reaction isadvantageously carried out in an anhydrous inert medium such as glacialacetic acid in an inert atmosphere. The temperature is in the range of0-100 C., preferably 30-80 C., and the reaction is conducted until asubstantial yield of the desired product has been precipitated, which isgenerally 6 hours or more depending upon the particular temperature. Theproduct is in the form of the tetratosylate, and if desired the freeamine can be produced by addition to a concentrated sulfuric acidsolution and after sufficient period for reaction, the solution iscooled to 0 C. and poured over ice to precipitate the free amine whichis further washed with deoxygenated water, then with deoxygenated 20%ammonium carbonate solution, again with deoxygenated water, dried underreduced pressure, and recrystallized from a solvent such as dimethylacetarnide to give a light yellow solid.

The 1,2-ditosylate of l,2,4,5-tetraaminobenzene is prepared by thecatalytic or chemical reduction of the ditosylate ofl,2-diamino-4,5-dinitrobenzene, which is prepared by the reaction of thecorresponding diamino-dinitrobenzene with toluene sulfonyl chloride orother appropriate sulfonyl chloride. The reduction is advantageouslyeffected by the gradual addition under nitrogen of an aqueous solutionof sodium hydrosulfite. The dinitro compound is advantageously reactedin solution in a solvent such as dimethyl acetamide. The reactiontemperature is advantageously in the range of 70-110 C. for a period ofapproximately l-3 hours. However temperatures as low as roomtemperature, or even 0 C., can also be used, in which case prolongedreaction times are required for substantial conversion. While highertemperatures than those indicated can be used, violent reactions mayresult, and the indicated temperatures are preferred since reaction issufiiciently rapid at those temperatures.

SPECIFIC EMBODIMENTS OF THE INVENTION The invention is illustrated bythe following examples. These examples are intended merely forillustrative purposes and are not intended to limit the scope of theinvention nor the manner in which it may be practiced. Unlessspecifically provided otherwise, reference to parts and percentages areby weight.

EXAMPLE I l,2-diamino-4,5- (p-toluenesulfamido) benzene T o a solutionof 15.2 g. (30.0 mmoles) of 1,2-dinitro- 4,5-(p-toluenesulfamido)benzenein 150 ml. of dimethylacetamide at C. there is added dropwise, undernitrogen, an aqueous solution 31.3 g. (180.0 mmoles) of sodiumhydrosulfite. After the addition is complete, the temperature ismaintained at 90 C. for two hours. The cooled reaction mixture is addedto 500 ml. of deoxygenated water to precipitate a white solid. Thematerial is collected, washed with water, and recrystallized frommethanol to afford 8.5 g. (63%) of the product, M.P. 238-239 C. Analysesshow: C, 53.83; H, 5.02; N, 12.46; as compared to theoretical values forC H N O of: C, 53.79; H, 4.96; N, 12.54.

EXAMPLE II 2,3,1 1,12-tetra- (p-toluenesulfamide) -diquinoxal-(2,3-e,2',3'-1)pyrene To a solution of 8.93 g. (20.0 mmoles) of1,2-diamino- 4,5-(p-toluenesulfamido)benzene in 250' ml. of glacialacetic acid there is added 2.62 g. (10.0 mmoles) of1,2,6,7-tetraketo-pyrene. The solution is stirred at 60 C. under anitrogen atmosphere, for eight hours. The yellow precipitate iscollected, washed with water, and recrystallized from dimethylacetamideto afford 8.90 g. (82%) of the product, M.P. 300 C. Analyses show:C,'62.04; H, 3.90; N, 10.17; as compared to theoretical values for C H NS O of: C, 62.08; H, 3.90; N, 10.34.

EXAMPLE III 2,3,11,12-tetraamino-diquinoxal(2,3-e,2',3'-)pyrene To 150ml. of concentrated sulfuric acid there is added 10.8 g. (10.0 mmoles)of 2,3,11,12-tetra-(p-toluenesulfamido)diquinoxal(2,3-e,2',3-1)pyrene.The solution is stirred at room temperature for six hours, cooled to 0C. and poured over ice to precipitate a dark red solid. The red materialis collected, washed with water, and added to a deoxygenated 20%ammonium carbonate solution to give a light yellow solid. The free amineis collected, washed with deoxygenated water, dried under reducedpressure, and recrystallized from dimethylacetamine to afford 4.43 g.(95%), MP. 300 C. Analyses show: C, 71.26; H, 3.97; N, 24.10; ascompared to theoretical values for C H N of: C, 72.08; H, 3.89; N,24.02.

EXAMPLE IV Polymer from l,4,5,8-naphthalenetetracarboxylic acid To 50 g.of deoxygenated polyphosphoric acid there is added, under a nitrogenatmosphere, 0.1543 g. (0.453 mmole) of1,4,5,8-naphthalenetetracarboxylic acid and 0.2117 g. (0.453 mmole) of2,3,11,12-tetramino-diquinoxal(2,3-3, 2,3-1)pyrene. The mixture isheated at the rate of 3 C./minute to 180 C. and maintained at thattemperature for hours. The solution is then allowed to cool to 30 C. andthe polymer is precipitated into 500 ml. of anhydrous methanol. Theisolated material is dissolved in methane sulfonic acid andreprecipitated into an hydrous methanol. The product, 0.29 g. (99%), hasan inherent viscosity of 0.36 dL/gm. in methane sulfonic acid (0.3g./l00 ml. at 30 C.). Analyses show: C, 72.76; H, 2.22; N, 16.42; ascompared to theoretical values for (C42H14Ng02) of: C, H, N, 16.91.

EXAMPLE IVa Polymer from the tetratosylate of the tetraamino To 100 g.of deoxygenated polyphosphoric acid is added, under a nitrogenatmosphere, 2.226 g. (0.212 mmole) of2,3,11,12-tetra(p-toluenesulfamido)diquinoxal(2,3-e,2',3'-l)pyrene. Themixture is heated to 80 C. and maintained at that temperature for 8hours. The dark blue solution is allowed to cool to room temperature and0.64 g. (0.212 mmole) of 1,4,5,8-naphthalenetetracarboxylic acid isadded. The mixture is then heated at the rate of 3 C./minute to 180 C.and held at that temperature for 10 hours. After the mixture has cooledto room temperature, it is precipitated into 1 liter of anhydrousmethanol. The material is collected, washed with methanol, dried underreduced pressure, and reprecipitated from methane sulfonic acid. Thepolymer, 1.3 g. (94% has an inherent viscosity of 0.70 dl./ g. inmethane sulfonic acid (0.3 g./100 ml. at 30 C.). Analysis calculated for(C H N O C, 76.12; H, 2.12; N, 16.91. Found: C, 75.69; H, 2.15; N,16.64.

6 EXAMPLE v The procedures of Examples IV and IVa are repeated a numberof times using individually, in place of the naphthalenetetra carboxylicacid, equivalent weights respectively of the dianhydrides of:

(a) 1,2,4,.5-benzene tetracarboxylic acid;

(b) 1,2,5,6-naphthalene tetracarboxylic acid; (0) 1,2,6,7-pyrenetetracarboxylic acid; and (d) o,o,o',o'-Diphenyl tetracarboxylic acid.

In each case ladder polymer are obtained.

EXAMPLE VI The procedure of Example IVa is repeated a number of timeswith similar polymers being produced using individually in place oftetratosyl derivative of the tetramino pyrene compound, an equivalentweight respectively of a number of corresponding compounds in which thetosyl groups are:

(a) p-Toluenesulfamide (b) Benzenesulfamide (c) Benzylsulfamide (d)Methylsulfamide (e) Cyclohexylsulfamide (f) p-Chlorobenzenesulfamide (g)Naphthalenesulfamide EXAMPLE VIa The procedure of Example IV is repeateda number of times with similar polymers being produced usingindividually in place of the tetraamino pyrene compound, an equivalentweight respectively of the following derivatives of the tetraaminopyrene compound:

(a) The tetrahydrochloride salt (b) The tetraphosphate salt (c) Thetetrasulfate salt EXAMPLE VII The procedure of Example IV is repeated anumber of times with similar polymers being produced using individuallyin place of the polyphosphoric reaction medium an equal weightrespectively of the following:

.(a) Dimethylformamide (b) Dimethylacetamido (c) Hexamethylphosphoramide(d) Tetramethyl urea (e) Dimethyl sulfoxide EXAMPLE VIII The procedureof Example I is repeated a number of times with similar results usingindividually in place of the dinitro-di(p-toluenesulfamido)benzene anequivalent weight respectively of the following ditosyl derivatives:

,(a) 1,2-dinitro-4,5-(benzenesulfamido)benzene (b)1,2-dinitro-4,5-(benzylsulfamido)benzene (c)1,2-dinitro-4,5-(methylsulfamido)benzene (d)1,2-dinitro-4,5-(cyclohexylsulfamido)benzene e) 1,2-dinitro-4,5-(p-Cl-Benzenesulfamido benzene (f)1,2-dinitro-4,5-(naphthalenesulfamdio)benzene EXAMPLE IX The procedureof Examples IV and War are repeated a number of times usingindividually, in place of the naphthalenetetracarboxylic acid,equivalent weights respectively of:

Ladder polymers are obtained with (a) and (b), but less rigid polymersare obtained with (c), (d) and (e).

-In the repeating unit structure of Formula III given above for thepolymers of this invention, the polymers produced in Examples IV, V andIX have the following respective structures for the tetravalent Arradical:

Ex. IV: Q

Ex. V(a): I

Ex. V(b): Q I Ex. V(c): Q

Ex. we I l Ex. IX(b): /N\ N Ex. lX(c): I

1 Ex. IX(d): l

Ex. IX(e): O l

The invention claimed is: 1. A compound having the formula in which saidTos represents RSO in which R is a radical selected from the groupconsisting of phenyl, tolyl, xylyl, naphthyl, diphenyl, m'ethylnaphthyl,benzyl, chlorophenyl, bromophenyl, iodophenyl, fluorophenyl,chloronaphthyl, chlorodiphenyl, methyl, ethyl, propyl, amyl, octyl,decyl dodecyl, octadecyl, cyclohexyl, cycloheptyl, methylcyclohexyl, andethylcycloheptyl.

2. The process of preparing a pyrene derivative of claim 1 comprisingthe step of reacting l,2-diamino-4,5- (p-toluenesulfamido)benzene with1,2,6,7-tetraketopyrene at a temperature in the range of 30100 C. for aperiod of at least 6 hours.

3. The process of claim 2 in which a subsequent treatment withconcentrated sulfuric acid is effected whereby the tosyl groups areremoved therefrom.

4. A compound having the formula 5. l,2-diamnio-4,5-(p-toluenesulfamido)benzene.

N NHTos N N HTOS References Cited UNITED STATES PATENTS NICHOLAS S.RIZZO, Primary Examiner US. Cl. X.R. 260--78 TF

